[PATCH 0/9] drm/vc4: Introduce locking and remove !KMS state access

[Maxime Ripard]

Hi,

This is a follow-up of the series here:
https://lore.kernel.org/all/20210924135530.1036564-1-maxime@cerno.tech/

and the discussion that occured here:
https://lore.kernel.org/all/YWgteNaNeaS9uWDe@phenom.ffwll.local/

The original series aimed at getting rid of the encoder->crtc pointer usage in
the vc4 HDMI driver, some regression was noticed and the following discussion
pointed out that we were doing a fair number of KMS state access outside of the
mode set path, which is disallowed and unsafe.

We already have a bug that was a result of that access which is fixed in the
second patch, but other instabilities might have occured without being
reported.

That series thus removes all those accesses, and add some locking in the
process.

Sudip, since that series changed very significantly since you last tested it,
could you give it a test run on the Codethink farm?

Let me know what you think,
Maxime

Maxime Ripard (9):
  drm/vc4: crtc: Drop feed_txp from state
  drm/vc4: Fix non-blocking commit getting stuck forever
  drm/vc4: crtc: Copy assigned channel to the CRTC
  drm/vc4: hdmi: Add a spinlock to protect register access
  drm/vc4: hdmi: Use a mutex to prevent concurrent framework access
  drm/vc4: hdmi: Prevent access to crtc->state outside of KMS
  drm/vc4: hdmi: Check the device state in prepare()
  drm/vc4: hdmi: Introduce an output_enabled flag
  drm/vc4: hdmi: Introduce a scdc_enabled flag

 drivers/gpu/drm/vc4/vc4_crtc.c      |  12 +-
 drivers/gpu/drm/vc4/vc4_drv.h       |  29 +-
 drivers/gpu/drm/vc4/vc4_hdmi.c      | 415 +++++++++++++++++++++++++---
 drivers/gpu/drm/vc4/vc4_hdmi.h      |  37 +++
 drivers/gpu/drm/vc4/vc4_hdmi_phy.c  |  37 +++
 drivers/gpu/drm/vc4/vc4_hdmi_regs.h |   2 +
 drivers/gpu/drm/vc4/vc4_hvs.c       |  26 +-
 drivers/gpu/drm/vc4/vc4_kms.c       |   3 +-
 drivers/gpu/drm/vc4/vc4_txp.c       |   4 +-
 9 files changed, 509 insertions(+), 56 deletions(-)

-- 
2.31.1